Three things stand out as first impressions to me about this beta:
The ability to customize the page using the Page Builder theme worked really well. I can’t say I’ve had as good an experience with this feature in Portal 7. In v7, there always seemed to be quirks that would not go away, like the changes not getting saved. In the beta version, this feature is working great. When you want to see a list of portlets you can add to the page, the list pops up very quickly.
Sign on with Open ID. Right on the log in page, there is an option to sign on to Portal using an Open ID from Yahoo or Google. While I don’t see this used all that much in the corporate world for intranets, I can see how this will be a good feature for consumer and even B2B sites.
Inline analytics can be displayed right on the page. You can add analytic tags to a page as an administrator and then see the metrics about that page right there. A little window pops up in a corner of the portlet window that will display metrics for each portlet. While I didn’t have this working in my portal just yet, the concept is pretty good. I’m sure I need to do a little tweaking to get it to display correctly.